Folding table

ABSTRACT

A table has a bottom plate having a bottom plate channel and an outer wall. A bottom plate lip is perpendicular to the outer wall. A top plate has a top plate lip overlying and parallel to the bottom plate lip. A lower end of a frame is in the bottom plate channel and an upper end of the frame is in contact with the top plate. An edge piece clamps the top plate lip and the bottom plate lip together. The edge piece extends entirely around a perimeter of the top plate.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.16/397,129, filed Apr. 29, 2019, which claims priority to Chineseinvention patent application number 201910115646.7, filed Feb. 15, 2019,which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a table, and to a composite table top.

BACKGROUND

The table is one of the most ubiquitous furniture pieces. The prior arttable top panel is traditionally made of wood. The use of wood hasdisadvantages: firstly, consumption of large amount of wood is notenvironmentally friendly; secondly, wood needs constant maintenance andthirdly, wood may not be used in some applications. Wood substitutessuch as fiberboard or flake board may also share similar defects.

To meet the needs of a modern household, a table top panel needs to betough, durable, lightweight and appealing. As consumers look for moreenvironment friendly alternatives, there are more and more examples oftable top panels made of synthetic materials.

There is a need for an improved table top made of a synthetic materialwith better applicability, low maintenance cost and better mechanicalproperties. There is also a need for improved aluminum folding tablesand methods of manufacture.

SUMMARY OF THE INVENTION

In a first aspect, a table includes a bottom plate having a bottom platechannel and an outer wall. A bottom plate lip is joined perpendicularlyto the outer wall. A top plate has a top plate lip overlying andparallel to the bottom plate lip. A lower end of a frame is positionedin the bottom plate channel and an upper end of the frame is in contactwith the top plate. A ductile edge piece has a first arm joined to asecond arm via a radius, with the ductile edge piece clamping the topplate lip and the bottom plate lip together. The ductile edge piece mayextend entirely around a perimeter of the top of the table.

Optionally, the frame is a rectangular metal tube, which may also extendentirely around a perimeter of the top of the table. The top plate lipmay be joined to the top plate via a joggle having an angle section, sothat a top surface of the edge piece is co-planer with the top plate.One or more sections of the bottom plate channel may have a step withthe frame on the step.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, the same element number indicates the same element ineach of the views. The drawings are provided by way of example and arenot intended at a limitation on the invention.

FIG. 1 is a top perspective view of a folding table.

FIG. 2 is a bottom perspective view of the table shown in FIG. 1.

FIG. 3 is a perspective view of the top of the table of FIG. 1 partiallycutaway for purpose of illustration.

FIG. 4 is an enlarged detail view of the cutaway section shown in FIG.3.

FIG. 5 is an exploded perspective view of the table top shown in FIG. 3.

FIG. 6 is a section view of the perimeter of the table shown in FIGS.1-5 showing steps of assembly.

FIG. 7 is a section view of the edge piece shown in FIGS. 1-5.

FIG. 8 is a section view of the edge piece of FIG. 7 in an intermediateassembly step.

FIG. 9 is a section view of the edge piece of FIG. 7 fully assembled tocomplete the table of FIGS. 1-5.

DETAILED DESCRIPTION

FIGS. 1-9 show a table 1501 with folding legs, that may be made of metalcomponents, such as aluminum. As shown in FIGS. 1-2, the table 1501 mayhave a first section 1502 attached to a second section 1504 via hinges1506, to allow the table 1501 to fold in half. A folding leg assembly1508 is attached to the outer end of each section 1502 and 1504.Specifically, as shown in FIGS. 1-2, each folding leg assembly 1508includes a pair of leg tubes 1510 pivotally attached to axles 1532 on aframe 1526. Leg insert tubes 1512 are joined by a brace 1514 and aretelescopically inserted into the leg tubes 1510. A spring loaded detentbutton 1516 projects into selected detent holes 1516 in the leg tubes1510, to allow the height of the table 1501 to be adjusted. With the leginsert tubes 1512 inserted fully into the leg tubes 1510, the table 1501has a minimum height, and the leg assembly 1508 is short enough to allowthe sections 1502 and 1504 to fold adjacent and parallel to each other,for compact storage or transport of the table 1501. A latch hinge 1520is pivotally attached to the frame 1526 and to each leg tube 1510 tolatch or hold the leg assemblies 1508 in the extended position shown inFIG. 1. A strap handle 1522 may optionally be provided on either section1502 or 1504 to allow the folded table 1501 to be more easily carried.Otherwise, the sections 1502 and 1504 may be substantially the same.

Turning to FIGS. 3 and 5, the top of the table 1501 includes a bottomplate 1524, a frame 1526, an edge piece 1528 and a top or face plate1530. The bottom plate 1524, the top plate 1530, the hinges 1506, theframe 1526, reinforcement tubes or plates and other features of thetable 1501 may be the same or similar to the tables described in U.S.Pat. No. 10,206,497, incorporated herein by reference. The bottom platemay be vacuum formed plastic, optionally having a pattern ofprojections, and a top surface of substantially each projection incontact with a lower surface of the top plate, as described in U.S. Pat.No. 10,206,497.

The frame 1526 may be a metal rectangular tube and may be generallycontinuous around the perimeter of the top of the table. The frame maybe bent at the corners of table, with a single seam or discontinuitywhere the opposite ends of the frame come together. The top plate 1530may be metal, such as aluminum, or it may be other materials such asplastic.

As shown in FIGS. 4 and 6-9, the bottom plate 1524 has a channel 1540around its perimeter. The channel 1540 may optionally have a step 1542.The step 1542 has a vertical surface extending up from, andperpendicularly joined into, a flat perimeter bottom surface 1558 of thebottom plate 1524. A vertical surface 1544 extends up from the step 1542to an interior bottom surface 1570 of the bottom plate 1524. A gap 1556having a height HH is formed between the interior bottom surface 1570and the bottom surface of the top plate 1530. As shown in FIG. 4, theprojections on the bottom plate 1524 project up across the gap 1556 tosupport the top plate 1530. The frame 1526 rests on step 1542, with theperimeter bottom surface 1558 spaced apart from the frame 1526 by abottom gap 1572 formed between the step 1542 and the outer wall 1546 ofthe bottom plate 1524. In the embodiment shown in FIGS. 1-5, only thechannels 1540 on the long sides of the table have a step 1542. The step1542 may be used to increase the height and the bending moment ofinertia of the channel 1540 on the long sides. The increased height ofthe step 1542 may also provide space for accommodating the folding legs.

In an alternative design shown in FIG. 4 and in dotted lines in FIG. 8,there is no step in the channel 1540. Rather, the channel is simplyrectangular to accommodate the rectangular frame 1526, and the entirebottom surface of the frame 1526 sits flat on bottom of the channel1558. The table 1501 may also be designed with the step 1542 along itsleft and right sides, and without the step 1542 at its front and rearsides.

A joggle 1550 is provided around the perimeter of the top plate 1530,with the joggle having an angled section 1552 joined to a top plate lip1554, at an acute angle. A bottom plate lip 1548 joined perpendicularlyto the outer wall 1546 is in contact with and parallel to the top platelip 1554. As shown in FIGS. 7 and 8 the edge piece 1528 has a first orlower arm 1560 joined to a second or upper arm 1562 through a radius1564. The edge piece 1528, which may be metal, such as aluminum, orother ductile material, is generally U-shaped or V-shaped. Ridges orprojections 1566 may be provided on the inner surfaces of the arms 1560and 1562. The edge piece 1528 may have a length sufficient to extendaround the entire perimeter of the top of the table. In this case theedge piece bends smoothly and tightly around the corners of the tabletop. This embodiment provides an aesthetic appearance, avoids creatingsharp edges or discontinuities, and can simplify manufacturing, as wellas improving the reliability of the attachment of the edge piece 1528.The first and second arms 1560 and 1562 typically each have a length LL,and the top plate lip 1554 and the bottom plate lip 1548 also eachhaving a length LL, as shown in FIG. 9. The length LL generally is lessthan the width of the frame 1526.

FIG. 8 shows the assembly of the edge piece 1528 during manufacture ofthe table 1501. The top plate lip 1554 and the bottom plate lip 1548 mayoptionally be initially attached to each other via adhesives, welding,fasteners, etc., with the frame 1526 in the channel 1540 and the frame1526 captive between the top plate 1530 and the bottom plate 1524.Alternatively, the top plate 1530 and the bottom plate 1524 mayalternatively be held in a fixture, with or without initially attachingthe top plate lip 1554 to the bottom plate lip 1548.

In one embodiment the edge piece is aluminum and is assembled in a coldworking process. The edge piece 1528 is shaped to fit the shape of theedge of the table. The edge piece 1528 is bent into an acute angle of20° to 40°, and typically about 30°. The edge piece 1528 is positionedover or around the top plate lip 1554 and the bottom plate lip 1548. Theedge piece 1528 is then pressed or rolled from the original or openposition shown in FIGS. 7 and 8, to the closed or crimped position shownin FIG. 9, wherein the edge piece 1528 clamps the top plate lip 1554 tothe bottom plate lip 1548. The pressing or clamping is performedsequentially or simultaneously around the entire perimeter of the top ofthe table. The edge piece 1528 is bent at right angles at the corners ofthe table sections 1502 and 1504, to allow the edge piece 1528 to extendcontinuously around the entire table top. The table top comprises thetop and bottom plates, the frame and the edge piece. If used, the ridges1566 project into the top plate lip 1554 and the bottom plate lip 1548to further secure the edge piece 1528 in place. As shown in FIG. 9, withthe table 1501 fully assembled, the top surface of the upper arm 1562 ofthe edge piece 1528 is co-planer with the top surface of the top plate1530. With the radius 1564 at the outer edge of the table top, the table1501 has a smooth continuous perimeter. The edge piece 1528 (andoptionally the 1526 frame as well) extends entirely around an upperperimeter area of the top plate, generally shown at 1580 in FIG. 9. Inthis embodiment no heat is used in forming or attaching the edge piece1528 and no adhesives are used. This avoids the disadvantages of usingadhesives. The edge piece 1528 may also help to close or seal thechannel 1540, reducing corrosion of internal components.

The present invention is not to be limited in scope by the specificembodiments described. Changes and modifications may be made to suchembodiments without departing from the true scope of the invention.Indeed, various modifications of the invention in addition to thoseshown and described herein will become apparent to those skilled in theart from the foregoing description and accompanying drawings. Suchmodifications are intended to fall within the scope of the appendedclaims. As used here, substantially equal to means within =/−10% of theparameter described.

The invention claimed is:
 1. A table comprising: a plastic bottom platehaving a bottom plate channel and an outer wall; a bottom plate lipjoined perpendicularly to the outer wall; a top plate having a top platelip overlying and parallel to the bottom plate lip; a metal frame havingan upper end in contact with the top plate, the frame comprising arectangular metal tube, a lower end of the frame in the bottom platechannel; a metal edge piece extending entirely and continuously aroundthe top plate lip and the bottom plate lip at a perimeter of the topplate, the edge piece pressed or rolled to clamp the top plate lip andthe bottom plate lip together.
 2. The table of claim 1 with the topplate lip joined to the top plate via a joggle having an angled sectionjoined to the top plate lip at an acute angle.
 3. The table of claim 1with the bottom plate channel having a step with the frame on the step.4. The table of claim 3 with the bottom plate including a verticalsurface extending up from the step to an interior bottom surface of thebottom plate and an inner sidewall of the rectangular metal tube is incontact with the vertical surface.
 5. The table of claim 4 furtherincluding gap between the interior bottom surface and the bottom surfaceof the top plate.
 6. The table of claim 5 wherein the bottom plate has apattern of projections extending across the gap, and a top surface ofsubstantially each projection is in contact with the bottom surface ofthe top plate.
 7. The table of claim 1 wherein the rectangular metaltube extends entirely around the perimeter of the top of the table. 8.The table of claim 7 wherein the top plate lip and the bottom plate lipeach have a length LL and wherein the edge piece has a first arm and asecond arm each having a length equal to LL, and further including abottom gap between a bottom surface of the channel and the frame, withthe bottom gap having a width substantially equal to LL.
 9. The table ofclaim 8 with a top surface of the first arm co-planer with a top surfaceof the top plate.
 10. The table of claim 8 wherein the bottom platechannel has a step, the frame is on the step, the bottom surface has aperimeter spaced apart from the frame by a bottom gap formed between thestep and the outer wall of the bottom plate.
 11. The table of claim 1with the edge piece has one or more ridges or projections.
 12. The tableof claim 1 wherein the frame has a bottom surface flush against a bottomof the channel.
 13. A table comprising: a plastic bottom plate having abottom plate channel and an outer wall; a bottom plate lip joinedperpendicularly to the outer wall; a top plate having a top plate lipoverlying and parallel to the bottom plate lip; a gap between aninterior bottom surface of the bottom plate and a bottom surface of thetop plate, the bottom plate having a pattern of projections extending upacross the gap, and a top surface of substantially each projection incontact with the bottom surface of the top plate; a rectangular metaltube frame having an upper end in contact with the top plate, a bottomsurface of the frame in the bottom plate channel; a metal edge piecehaving a first arm joined to a second arm via a radius, the metal edgepiece clamping the top plate lip and the bottom plate lip together, andwith the metal edge piece extending around a perimeter of the top plate.14. The table of claim 13 wherein the bottom plate channel has a stepand a bottom surface of the rectangular metal tube frame is on the step.15. The table of claim 13 wherein the edge piece has one or more ridgesor projections.
 16. The table of claim 13 with a top surface of thefirst arm co-planer with a top surface of the top plate.
 17. The tableof claim 13 wherein the metal edge piece is pressed or rolled to clampthe top plate lip and the bottom plate lip together.
 18. The table ofclaim 13 with the bottom plate channel having a step with the frame onthe step.
 19. A table comprising: a bottom plate having a pattern ofprojections, a bottom plate channel and an outer wall; a bottom platelip joined to a top end of the outer wall; a top plate having a topplate lip; a top surface of substantially each projection in contactwith a lower surface of the top plate; a tubular metal frame, a lowerend of the metal frame in the bottom plate channel and an upper end ofthe frame in contact with the top plate, the outer wall in parallel toone side of the tubular metal frame; a U-shaped metal edge piece havinga first arm joined to a second arm via a radius, the edge piece clampingthe top plate lip and the bottom plate lip together; the edge piece andthe tubular metal frame extending around an upper perimeter area of thetop plate; and a leg assembly pivotally attached to the frame.
 20. Atable comprising: a bottom plate having a bottom plate channel and anouter wall; a bottom plate lip joined perpendicularly to the outer wall;a top plate having a top plate lip overlying and parallel to the bottomplate lip; a frame having an upper end in contact with the top plate;the bottom plate channel having a step with the frame on the step; anedge piece clamps the top plate lip and the bottom plate lip together;the edge piece extends around a perimeter of the top plate; the tablehaving two longer sides and two shorter sides and the bottom platechannel having a step only on the two longer sides.